fix clippy.

analytic_engine/src/manifest/details.rs

@@ -21,7 +21,7 @@ use macros::define_result;
 use object_store::{ObjectStoreRef, Path};
 use parquet::data_type::AsBytes;
 use prometheus::{
-    exponential_buckets, register_histogram, register_int_counter, Histogram, IntCounter,
+    exponential_buckets, register_histogram, Histogram,
 };
 use prost::Message;
 use serde::{Deserialize, Serialize};